The invention relates to a method for regulating the driving dynamics of a vehicle, wherein a specific torque acts on at least one wheel of the vehicle based on control of a clutch transmitting torque to the wheel and/or as a result of control of a differential distributing torque to said wheel plus at least one additional wheel.
The present invention also relates to a device for regulating the driving dynamics of a vehicle, comprising at least one actuator for controlling a clutch that transmits torque to a wheel of the vehicle and/or at least one actuator for controlling a differential that distributes torque to the wheels of the vehicle.
It is known from the state of the art that electronically controllable elements can be incorporated into the drive train of a motor vehicle to distribute the driving power among the individual wheels in a targeted manner. Known options for controlling a torque transmitted to a wheel range from controlling lockable differentials on a driven axle of the vehicle to an individual torque distribution to each wheel in the case of four-wheel drive vehicles.
A generic method and a generic device are derived from Unexamined German Patent DE 198 00 327 A1, for example, which relates to a driving power control system in a four-wheel drive vehicle in which the maximum torque transmitted to a right and left wheel by a right and left clutch is set to be lower with an increase in vehicle speed. Furthermore, a rear differential is capable of generating a difference between engagement forces of the right and left clutches to control the steering characteristic of the vehicle and in particular to eliminate any tendency of the vehicle to oversteer or understeer. This is recognized on the basis of a comparison of a calculated reference yaw rate with a detected instantaneous yaw rate of the vehicle.
International Patent Application WO 02/09965 A1 discloses another generic method and another generic device with which rotational speeds of individual wheels are adapted to driving maneuvers initiated by the driver, said maneuvers being recognized on the basis of driving state parameters detected by sensors. Differentials are used to control the rotational speeds.
Through measures intervening in the drive train, such as those performed with the aforementioned methods and devices, for example, the vehicle following performance is greatly improved in many driving situations. In particular, a reduction in a tendency to understeer, which can be achieved through a targeted distribution of torque among the individual wheels, leads to more direct vehicle responses and thus to increased safety, in particular in swerving maneuvers to avoid an object and to an increase in the driving pleasure perceived by the driver.
However, the known methods have the disadvantage that physical limits of a stable driving performance are taken into account only inadequately or not at all and the regulating intervention measures provide little or no support for the driver in the limit range in terms of driving dynamics. An ESP system that intervenes in the driving dynamics regulation in safety-critical driving states for implementation of an electronic stability program (ESP) is often perceived by the driver as unexpected and uncomfortable.